This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.
Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
When these two medicines are taken together, your body may not process astemizole or terfenadine properly.
What might happen:
Your blood levels of astemizole or terfenadine may increase and cause life-threatening effects to your heart. You may be at higher risk if you have had previous heart problems.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) as soon as possible about taking these two medicines together. They may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
1.Zyflo (zileuton) US prescribing information. Abbott Laboratories October, 2000.
2.Seldane (terfenadine) US prescribing information. Hoechst-Marion Roussel September, 1997.
3.Dear Doctor Letter. Janssen Pharmaceutica Products, L.P. February 1998.